To the Editor.
—In the June Archives Blackshear et al1 observed that renal insufficiency induced by nonsteroidal anti-inflammatory drugs is more frequent in patients with the following risk factors: advanced age, atherosclerotic cardiovascular disease, and use of diuretic drugs.We would like to add sulfinpyrazone to the list of these nonsteroidal anti-inflammatory drugs, which can lead to renal dysfunction in these clinical settings. Although devoid of anti-inflammatory activity, sulfinpyrazone inhibits prostaglandin synthesis not only in the platelets, but also in the kidney.2-4 We recently reviewed the reports of acute renal failure during sulfinpyrazone therapy. Eighteen patients who received this drug after myocardial infarction showed an average serum creatinine rising from 1.3 to 6.3 mg/dL. Their mean age was 60 years and eight of them had concomitant diuretic therapy.5 Sulfinpyrazone therapy has also been advocated early after coronary bypass surgery. It was considered safe, but renal function was